Single Process Research Articles

Investigation on axial evolution of particle group and conversion of a single coal particle in an impinging entrained-flow gasifier

Based on a bench-scale impinging entrained-flow gasifier and visualization system, the conversion of particle group and a single coal particle in the impinging-flow zone below the burner plane is investigated in-situ. The axial evolution of particle group including particle size, particle concentration, velocity field and spatial distribution is characterized with image processing algorithm and statistical method. The particle fragmentation, single particle conversion process and volatile oxidation behavior are discussed. The results indicate that the Sauter mean diameter (SMD) is distributed in 560–720 µm in all statistical regions, and the particle concentration is distributed in 20,000–360,000. With the axial downward movement of the particle group, the SMD, particle concentration and spatial distribution frequency show an overall decreasing trend. The proportion of particles ranging in the velocity interval of 0–4 m/s increases in the three impinging-flow zones, which are 85.76 %, 92.33 % and 97.88 %, respectively. The fragmentation mode of a single coal particle can be classified into central fragmentation and peripheral fragmentation. The occurrence probabilities of the two modes in the upper impinging-flow zone are more than one-third, indicating that the particles tend to be fragmented near the burner plane. The conversion of a single coal particle can be divided into heat up and pyrolysis, volatile oxidation, volatile/char oxidation and char oxidation. In the upper impinging-flow zone, less than 30 % of the particles are in volatile oxidation stage, while about 50 % of the particles are in char oxidation stage. With the axial downward movement of the particle group, the proportion of particles in char oxidation stage decreases, while the proportion of particles in volatile oxidation stage shows an opposite trend. A macroscopic description of ignition and propagation of particle volatile flame is proposed. The propagation of volatile flame between singles particles can be extended to the propagation of volatile flame within particle groups.

Guar gum as a microbially degradable component for an oral colon delivery system based on a combination strategy: formulation and in vitro evaluation.

Oral colon delivery has widely been pursued exploiting naturally occurring polysaccharides degraded by the resident microbiota. However, their hydrophilicity may hinder the targeting performance. The aim of the present study was to manufacture and evaluate a double-coated delivery system leveraging intestinal microbiota, pH, and transit time for reliable colonic release. This system comprised a tablet core, a hydroxypropyl methylcellulose (HPMC) inner layer and an outer coating based on Eudragit® S and guar gum. The tablets were loaded with paracetamol, selected as a tracer drug because of the well-known analytical profile and lack of major effects on bacterial viability. The HPMC and Eudragit® S layers were applied by film-coating. Tested for in vitro release, the double-coated systems showed gastroresistance in 0.1 N HCl followed by lag phases of consistent duration in phosphate buffer pH 7.4, imparted by the HPMC layer and synergistically extended by the Eudragit® S/guar gum one. In simulated colonic fluid with fecal bacteria from an inflammatory bowel disease patient, release was faster than in the presence of β-mannanase and in control culture medium. Thebacteria-containingfluid was obtained by an experimental procedure making multiple tests possible from a single sampling and processing run. Thus, the study conducted proved the feasibility of the delivery system and ability of guar gum to trigger release in the presence of colon bacteria without impairing the barrier properties of the coating. Finally, it allowed an advantageous simulated colonicfluid preparation procedure to be set up, reducing the time, costs, and complexity of testing and enhancing replicability.

A sliding sequence importance resample filtering method for rolling bearings remaining useful life prediction based on two Wiener-process models

The remaining useful life (RUL) prediction of rolling bearings is an important part of prognostic and health management of mechanical systems. The model based on Wiener process can describe the time variability in the degradation process of bearings. However, in practical engineering, the degradation trends of bearings are often inconsistent, and it is difficult to fit the actual degradation trends of bearings with a single Wiener process model-based filtering method. Therefore, to improve the generalization ability, this paper uses linear model and exponential model based on Wiener process to predict bearing RUL. A sliding sequence importance resample filtering algorithm is proposed to track the degradation state of the bearing and reduce the prediction error by combining the two degradation models. Last, the superiority and effectiveness of the proposed method are illustrated by comparing with other commonly used RUL prediction methods on the basis of PRONOSTIA dataset.

New coupling technology of phenols extraction in coal tar and carbon dioxide capture: Modeling, optimization and techno-economic analysis

A new coupling process for highly efficient extracting phenols from coal tar and capturing carbon dioxide in exhaust gas employing aqueous amine was developed, which improved the shortcomings of high cost and environment pollution of single industrial process by process coupling and strengthening. The cyclic experiment of this process with monoethanolamine solution as extractant reached a stable state after 4 cycles. Under the steady-state, the total extraction yield of phenols and the total recovery yield of monoethanolamine and water were 100%, 98.8% and 90.9%, respectively. In addition, the empirical and semi-empirical models based on the experimental and literature data were constructed, and the models were linked to Aspen Plus software to simulate and optimize the coupling process. The optimization results showed that the unit production cost of present green process was 274.79 CNY·t−1, which only 25.4% and 65.6% of the cost for the traditional and improved industrial processes, respectively. Especially, the consumption of mineral resources and pollutant emissions in this process were reduced compared to the industrial processes. This work provides an industrially promising method for extracting phenolic compounds from coal tar and synergistically capturing carbon dioxide in industrial exhaust gas, and lays an engineering foundation.

Mechanism Analysis of Discharge Energy in the Electrostatic-Field-Induced Electrolyte Jet Micro-EDM.

The discharge energy determines the machining resolution, minimum processable feature size, and surface roughness, which makes it a hot research topic in the microelectrical discharge machining (EDM) field. In this paper, a kind of novel discharge-energy-generation method in micro-EDM is investigated. In this method, the opposite induced charges on the electrolyte jet and workpiece serve as the source of the discharge energy. The operating mechanism of this discharge energy is revealed by analyzing the equivalent discharge circuit. The unique discharge current and voltage between the electrolyte jet and the workpiece are sampled and investigated. In contrast with the pulsating energy in conventional EDM, this study shows that the direct current (DC) voltage source can automatically generate a continuously periodical pulsating discharge in the electrostatic-field-induced electrolyte jet (E-Jet) EDM process. After further analyzing the electric signals in a single discharge process, it can be found that the interelectrode voltage experienced a continuous sharp electric breakdown, a nearly unchanging process, and a fast exponential recharging process. The discharge frequency increases as the electrolyte concentration and interelectrode voltage increase but decreases as the interelectrode distance increases. The discharge energy per pulse increases with the increasing interelectrode distance and electrolyte concentration but with the decreasing interelectrode voltage. Finally, the electrostatic-field-induced discharge-energy generation and change mechanisms are revealed, which provides a feasible method for micro-EDM with continuous tiny pulsed energy only using the DC power supply.

DRT analysis and transmission line modeling of ceria based electrodes for solid oxide cells

For the analysis of performance limiting processes in various electrochemical systems like lithium ion batteries, polymer electrolyte membrane fuel cells or solid oxide cells, impedance spectroscopy is a powerful tool. The distribution of relaxation times (DRT) enables the deconvolution of the polarization processes in the spectrum. The simple approach, to correlate each peak in the DRT with a single polarization process fails for multiphase electrodes as the complex coupling of electronic, ionic and transport of different species by spatially distributed charge transfer reactions leads to a number of correlated peaks in the DRT.In this contribution such coupling of transport and reaction is analyzed for ceria based fuel electrodes applied in solid oxide cells. A physicochemically meaningful two-channel transmission line model is developed. Due to the ambiguity of impedance spectra and DRT, the straightforward approach of fitting this model to measured spectra does not allow an unambiguous model parameterization. Additional methods as conductivity measurements and focused ion beam-tomography are indispensable to obtain physicochemically meaningful parameters to be applied in the fitting procedure. With this parameterization approach DRT based modeling becomes feasible and ionic/electronic transport resistances and area specific charge transfer resistance of the ceria surface can be quantified.

Enhancing the Heterologous Expression of a Thermophilic Endoglucanase and Its Cost-Effective Production in Pichia pastoris Using Multiple Strategies.

Although Pichia pastoris was successfully used for heterologous gene expression for more than twenty years, many factors influencing protein expression remain unclear. Here, we optimized the expression of a thermophilic endoglucanase from Thermothielavioides terrestris (TtCel45A) for cost-effective production in Pichia pastoris. To achieve this, we established a multifactorial regulation strategy that involved selecting a genome-editing system, utilizing neutral loci, incorporating multiple copies of the heterologous expression cassette, and optimizing high-density fermentation for the co-production of single-cell protein (SCP). Notably, even though all neutral sites were used, there was still a slight difference in the enzymatic activity of heterologously expressed TtCel45A. Interestingly, the optimal gene copy number for the chromosomal expression of TtCel45A was found to be three, indicating limitations in translational capacity, post-translational processing, and secretion, ultimately impacting protein yields in P. pastoris. We suggest that multiple parameters might influence a kinetic competition between protein elongation and mRNA degradation. During high-density fermentation, the highest protein concentration and endoglucanase activity of TtCel45A with three copies reached 15.8 g/L and 9640 IU/mL, respectively. At the same time, the remaining SCP of P. pastoris exhibited a crude protein and amino acid content of up to 59.32% and 46.98%, respectively. These findings suggested that SCP from P. pastoris holds great promise as a sustainable and cost-effective alternative for meeting the global protein demand, while also enabling the production of thermophilic TtCel45A in a single industrial process.

Enhancing simultaneous desulfurization and denitrification efficiency of cement kiln exhaust gas via co-catalytic Fenton oxidation process

Traditional Fenton reaction can hardly achieve the simultaneous desulfurization (de-SO2) and denitrification (de-NOx) for the cement kiln exhaust gas, due to the low production of free radicals as the limited Fe2+/Fe3+ cycle. Herein, an enhanced Fenton oxidation process was developed to remove SO2 and NOx efficiently, through improved Fe3+/Fe2+ conversion via the co-catalytic effect of metal sulfides and multi-metal oxysulfides. Among them, the WS2/Fe2+/H2O2 system showed the de-SO2 and de-NOx efficiency of 100% and 83.5%, respectively, and nearly no decrease in efficiency after 300 min. The highest initial de-NOx efficiency of 95.3% was achieved when Co-Mo-W-(5-4) served as co-catalyst, and the efficiency and stability were further improved after coupling NaSO3 solution absorption. Moreover, •OH was identified as the primary reactive oxygen species (ROS) for SO2 and NOx oxidation, then a reaction mechanism focusing on the reactive oxygen species (ROS) generation as well as NOx and SO2 removal was proposed based on EPR, XPS, FTIR, and Raman analysis. Thus, the results provide theoretical and technical support for developing de-SO2 and de-NOx technologies of cement kiln exhaust gas within a single process to achieve cleaner production.

Chemical Exchange Rate Study by NMR CPMG Method

Analysis of the NMR CPMG method is presented that enables direct sampling of the spectral-density function of the chemical exchange processes. The approach is demonstrated on a solution of sucrose in water. The result confirms that the method can provide insight into the details of the dynamics of molecular conformations beyond a single-parameter description by an exchange rate. The results of the method are not limited to a single exchange process but can be of advantage if a large and potentially unknown number of exchange processes is contributing to the dynamics of a spin system.

Patterns in staff reported surgical instrument errors point to failures in visualization as a critically weak point in sterile processing of surgical instruments

BackgroundSurgical Instrument Errors (missing, broken, bioburden/contamination etc.) account for significant delays in the operating room. During sterile processing, instruments must be inspected for correctness, functionality, and cleanliness (bioburden) prior to packaging for sterilization. The environment where these tasks are performed is typically high stress and high throughput. There is a growing body of research in human performance that indicates that under stress, the skill of human visualization (inspection and identification) deteriorates. Furthermore, error modeling of sterile processing of surgical instruments suggests that the tasks at highest risk for errors involve human visualization. Reporting of Surgical Instrument Errors at our institution falls to OR staff and, during the period of this study, was done through a mechanism termed the Patient safety notice or PSN. PSNs are filed via computer through the healthcare system website. There is no integration or linkage of the PSN to the electronic medical record and information in all fields must be typed in as it does not automatically populate. We hypothesized that the most common PSNs reporting Surgical Instrument Errors would involve tasks of visualization (inspection, identification). Accordingly, the most common reported Surgical Instrument Errors would be missing instruments, bioburden/contamination, and broken instruments. We also hypothesized that due to the complexity and lack of both data automation and integration with the electronic medical record in filing PSNs, the majority of PSNs reporting Surgical Instrument Errors would be incomplete. To test these two hypotheses, we analyzed one year's worth staff reported Surgical Instrument Error rates at two hospitals with the operating rooms at both locations serviced by a single sterile processing facility. MethodsThis study was conducted at a major healthcare center that houses 38 ORs located at 3 sites (Children's (8), Adult inpatient (24) and Adult outpatient (6)) all of which share a sterile processing facility. Staff reported Patient Safety Notices (PSNs), a reporting mechanism for safety events, were collected from July 2019 through June of 2020. PSNs reporting the following Surgical Instrument Errors: missing instrument (listed on the count sheet but absent from the tray), broken instrument, assembly or packaging error, wrong instrument, failed sterilization/bioburden/contamination, fleet management (trays missing), extra instrument and transport errors were identified. Raw annual rates of reported Surgical Instrument Errors were determined for each hospital. Rates per surgical service line (percent affected cases) per hospital were then determined by dividing the annual number of reported errors per service by the annual number of cases per service line. Whether the instrument error affected the sterile field was determined as well. An analysis of bioburden/contamination error rates and Surgical Instrument Error types by hospital was also determined. Results368 PSNs reporting 419 Surgical Instrument Errors were identified over a 12-month period (0.0432 errors/OR/elective OR day). The majority of reported errors (83 %) had to do with failures in inspection (bioburden/contamination) or in tracking and identification (missing). At both hospitals, cardiovascular surgery had the highest reported error rates per case (4.47 % of cases affected at the Adult hospital and 3.68 % of cases affected at the Children's hospital). In only 64 instances was the sterile field reported to be affected by the error. Bioburden/contamination was the most commonly reported instrument error (68.97 %) with the most common types of bioburden/contamination being debris, blood and tissue, failed instrument cleaning due to incomplete disassembly and the presence of hair. Overall, only 20.4 % of PSN had all fields filled to completion and 15 % were submitted days after the event (average of 12.70 ± 27.97 days, median of 2 days). Conclusionsthe data from this study indicates that failure in human visualization vis-à-vis inspection and identification are the root cause of the majority (83 %) of staff reported Surgical Instrument Errors. This manifests primarily through problems with bioburden/contamination and missing instruments. Implementation of technologies to improve inspection and identification and ultimately tracking of surgical instruments should substantially reduce Surgical Instrument Error rates. Furthermore, staff dependent reporting of these errors is rarely done to completion and a significant portion of events are reported days after an event. These latter findings suggest that the process is cumbersome and likely impedes accurate and timely reporting and may results in underreporting of Surgical Instrument Errors.

Evolution at multiple processing levels underlies odor-guided behavior in the genus Drosophila

Olfaction is a fundamental sense guiding animals to their food. How the olfactory system evolves and influences behavior is still poorly understood. Here, we selected five drosophilid species, including Drosophila melanogaster, inhabiting different ecological niches to compare their olfactory systems at multiple levels. We first identified ecologically relevant natural food odorants from every species and established species-specific odorant preferences. To compare odor coding in sensory neurons, we analyzed the antennal lobe (AL) structure, generated glomerular atlases, and developed GCaMP transgenic lines for all species. Although subsets of glomeruli showed distinct tuning profiles, odorants inducing species-specific preferences were coded generally similarly. Species distantly related or occupying different habitats showed more evident differences in odor coding, and further analysis revealed that changes in olfactory receptor (OR) sequences partially explain these differences. Our results demonstrate that genetic distance in phylogeny and ecological niche occupancy are key determinants in the evolution of ORs, AL structures, odor coding, and behavior. Interestingly, changes in odor coding among species could not be explained by evolutionary changes at a single olfactory processing level but rather are a complex phenomenon based on changes at multiple levels.

Principles of Organization of Correctional Care for Children with Cerebral Palsy

The purpose of this work was to analyze the structure of the organization of forms, methods and ways to optimize the process of correctional care for children diagnosed with cerebral palsy. Currently, there are some problems in the organization of the process of comprehensive rehabilitation of children suffering from cerebral palsy. It manifests itself in the weak elaboration of the general methodological foundations, insufficient level of interaction between the links of the structure and the lack of general monitoring of the quality of the impacts and evaluation of the effectiveness of rehabilitation measures. It is assumed that the results will allow to determine the potential structure of the organization of correctional care for children with cerebral palsy and will help to more accurately identify problem areas in the process of socio-pedagogical and clinical-psychological support of such children. In the presented article were formulated the main approaches which help to take a new look at the system of special education and training of children with cerebral palsy. First of all, the development and implementation of a system of effective phased care will be most effective if it will be built on the basis of early diagnosis and systematic medical, pedagogical and social work with such children. In addition, it is necessary to improve the existing system of assistance to children diagnosed with cerebral palsy by creating relevant models based on the principles of an open space for interdepartmental and interdisciplinary interaction. This requires programs based on continuous study of the child and representing a single process of comprehensive rehabilitation with the function of constant monitoring

Rethinking Aerobic Respiration in the Hyporheic Zone under Variation in Carbon and Nitrogen Stoichiometry.

Hyporheic zones (HZs)─zones of groundwater-surface water mixing─are hotspots for dissolved organic matter (DOM) and nutrient cycling that can disproportionately impact aquatic ecosystem functions. However, the mechanisms affecting DOM metabolism through space and time in HZs remain poorly understood. To resolve this gap, we investigate a recently proposed theory describing trade-offs between carbon (C) and nitrogen (N) limitations as a key regulator of HZ metabolism. We propose that throughout the extent of the HZ, a single process like aerobic respiration (AR) can be limited by both DOM thermodynamics and N content due to highly variable C/N ratios over short distances (centimeter scale). To investigate this theory, we used a large flume, continuous optode measurements of dissolved oxygen (DO), and spatially and temporally resolved molecular analysis of DOM. Carbon and N limitations were inferred from changes in the elemental stoichiometric ratio. We show sequential, depth-stratified relationships of DO with DOM thermodynamics and organic N that change across centimeter scales. In the shallow HZ with low C/N, DO was associated with the thermodynamics of DOM, while deeper in the HZ with higher C/N, DO was associated with inferred biochemical reactions involving organic N. Collectively, our results suggest that there are multiple competing processes that limit AR in the HZ. Resolving this spatiotemporal variation could improve predictions from mechanistic models, either via more highly resolved grid cells or by representing AR colimitation by DOM thermodynamics and organic N.

An electromechanical dynamic stiffness matrix of piezoelectric stacks for systematic design of micro/nano motion actuators

Piezoelectric stacks have proved to be effective for micro/nano motion actuators with large blocking forces. A critical problem is to build their electro-mechanical model for systematic design of statics and dynamics including piezoelectric hysteresis and elasto-kinematics of compliant mechanisms. To ease this issue, this paper proposes a new electro-mechanical dynamic stiffness matrix of piezoelectric stacks to enable a systematic analysis. Positive and inverse piezoelectric effects are included into the dynamic stiffness matrix of Timoshenko beams in the form of Taylor’s series with a clear definition of physical parameters. Consequently, the Jacobian matrix, input/output stiffness, natural frequencies, frequency-domain spectrums of mechanical displacement and electrical impedance as well as the time-domain response of piezoelectric hysteresis can be fully obtained with a single modeling process. Particularly, the time-domain response in the presence of piezoelectric rate-dependent hysteresis and dynamic resonance behaviors of compliant mechanisms is captured in a parameter-insightful way but not the manner in Hammerstein hysteresis model with a black-box transfer function. Experiments on a proof-of-concept prototype of precision positioning stage verify the easy operation and satisfying prediction accuracy of the presented approach.

A low-cost and sustainable solution for nitrate removal from secondary effluent: Macroporous ion exchange resin treatment

Macroporous ion exchange resin has excellent selectivity to nitrogen (N), phosphorus (P) and partially soluble refractory organic compounds contained in the secondary effluent of wastewater treatment plants (WWTP). In this study, macroporous ion exchange resins were chosen as an alternative to single biochemical nitrogen removal processes. Various conditions were examined to optimize adsorption performance, and the adsorption mechanism was explored through isotherm fitting, thermodynamic parameter calculation, and kinetic analysis. The experiment demonstrated that the resin exhibited strong selectivity for nitrate (NO3−) and achieved an equilibrium adsorption amount of 9.8924 mg/g and an equilibrium adsorption time of 60 min at 25 °C. The resin denitrification pilot plant demonstrated stable operation for two months and achieved COD<20 mg/L, TN < 1.5 mg/L, and NH4+-N<0.5 mg/L. The removal rates of COD, TP, NH4+-N, NO3−-N, and TN were 41.65%, 42.96%, 55.37%, 91.8%, and 90.81%, respectively. After the resin was regenerated, the removal rates of NO3−-N, TN and the regeneration recovery rate were above 90%. Through cost analysis, the treatment cost of the pilot plant is only 0.104 $/m3. This study presents a practical, low-cost, and efficient treatment method for the deep treatment of secondary effluent from WWTP in practical engineering, providing new ideas and theoretical guidance.

Novel strategy to enhance the biological treatment of coal chemical wastewater by nano-zero valent ironloaded fly ash-based activated carbonassisted activated sludge process.

Industrial waste as novel conductive mediator was applied for wastewater treatment as a novel strategy for both waste recycling and sustainable development of wastewater treatment. In this study, nanoscale zero valent iron-loaded fly ash-based activated carbon (nZVI@FABAC) was prepared and applied to enhancing activated sludge (AS) process for coal chemical wastewater (CCW) treatment. The results demonstrated that the removal efficiencies of COD and total phenols (TPh) in nZVI@FABAC/AS process reached about 83.96 and 85.17%, which increased 52.51 and 31.52% compared with the single AS process, respectively. And the acute toxic unit value of CCW was reduced by 88.24% after nZVI@FABAC/AS process treatment. The various functional bacteria including phenol-degrading bacteria (Comamonas and Acinetobacter), electroactive bacteria (Geobacter), and iron reduction bacteria (Geothrix) were enriched in the nZVI@FABAC/AS process, which provided various electron transfer pathways to improve the degradation of toxic organics in CCW. Accordingly, nZVI@FABAC/AS process provided a promising and sustainable way for industrial wastewater treatment.

Diffusion theory of the antipodal "shadow" mode in continuous-outcome, coherent-motion decisions.

Continuous-outcome decisions, in which responses are made on continuous scales, are increasingly used to study perception and memory for stimulus attributes like color, orientation, and motion. This interest has led to the development of models of continuous-outcome decision processes like the circular diffusion model that predict joint distributions of decision outcomes and response times (RTs). We use the circular diffusion model and a new spherical generalization of it to model performance in a continuous-outcome version of the random-dot motion task. The task is a benchmark test of decision models because it yields bimodal distributions of decision outcomes: In addition to a peak or mode in the true direction of motion, there is a secondary, antipodal, mode at 180° to the true direction. Models like the circular diffusion model, in which evidence is accumulated by a single process, are thought to be unable to predict bimodality. We compared diffusion models for the continuous motion task in which evidence is accumulated in either a two-dimensional (2D) or a three-dimensional (3D) representational space. We found that performance was well described by a spherical (3D) diffusion model in which the drift rate encodes perceived motion direction and strength and the points on the bounding sphere representing the decision criterion are projected onto a 2D circle to make a response. A model with an antipodal component of drift rate and drift-rate variability successfully predicted bimodal distributions of decision outcomes and the joint distributions of decision outcomes and RT for individual participants. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Optical soliton solutions of the coupled Radhakrishnan-Kundu-Lakshmanan equation by using the extended direct algebraic approach

The analytical soliton solutions place a lot of value on birefringent fibres. The major goal of this study is to generate novel forms of soliton solutions for the Radhakrishnan-Kundu-Lakshmanan equation, which depicts unstable optical solitons that arise from optical propagations using birefringent fibres. The (presumably new) extended direct algebraic (EDA) technique is used here to extract a large number of solutions for RKLE. It gives soliton solutions up to thirty-seven, which essentially correspond to all soliton families. This method's ability to determine many sorts of solutions through a single process is one of its key advantages. Additionally, it is simple to infer that the technique employed in this study is really straightforward yet one of the quite effective approaches to solving nonlinear partial differential equations so, this novel extended direct algebraic (EDA) technique may be regarded as a comprehensive procedure. The resulting solutions are found to be hyperbolic, periodic, trigonometric, bright and dark, combined bright-dark, and W-shaped soliton, and these solutions are visually represented by means of 2D, 3D, and density plots. The present study can be extended to investigate several other nonlinear systems to understand the physical insights of the optical propagations through birefringent fibre.

IPv6 flood attack detection based on epsilon greedy optimized Q learning in single board computer

&lt;span lang="EN-US"&gt;Internet of things is a technology that allows communication between devices within a network. Since this technology depends on a network to communicate, the vulnerability of the exposed devices increased significantly. Furthermore, the use of internet protocol version 6 (IPv6) as the successor to internet protocol version 4 (IPv4) as a communication protocol constituted a significant problem for the network. Hence, this protocol was exploitable for flooding attacks in the IPv6 network. As a countermeasure against the flood, this study designed an IPv6 flood attack detection by using epsilon greedy optimized Q learning algorithm. According to the evaluation, the agent with epsilon 0.1 could reach 98% of accuracy and 11,550 rewards compared to the other agents. When compared to control models, the agent is also the most accurate compared to other algorithms followed by neural network (NN), K-nearest neighbors (KNN), decision tree (DT), naive Bayes (NB), and support vector machine (SVM). Besides that, the agent used more than 99% of a single central processing unit (CPU). Hence, the agent will not hinder internet of things (IoT) devices with multiple processors. Thus, we concluded that the proposed agent has high accuracy and feasibility in a single board computer (SBC).&lt;/span&gt;

Role-Exchange Playing: An Exploration of Role-Playing Effects for Anti-Bullying in Immersive Virtual Environments.

Role-playing is widely used in many areas, such as psychotherapy and behavior change. However, few studies have explored the possible effects of playing multiple roles in a single role-playing process. We propose a new role-playing paradigm, called role-exchange playing, in which a user plays two opposite roles successively in the same simulated event for better cognitive enhancement. We designed an experiment with this novel role-exchange playing strategy in the immersive virtual environments; and school bullying was chosen as a scenario in this case. A total of 234 middle/high school students were enrolled in the mixed-design experiment. From the user study, we found that through role-exchange, students developed more morally correct opinions about bullying, as well as increased empathy and willingness to engage in supportive behavior. They also showed increased commitment to stopping bullying others. Our role-exchange paradigm could achieve a better effect than traditional role-playing methods in situations where participants have no prior experience associated with the roles they play. Therefore, using role-exchange playing in the immersive virtual environments to educate minors can help prevent them from bullying others in the real world. Our study indicates a positive significance in moral education of teenagers. Our role-exchange playing may have the potential to be extended to such applications as counseling, therapy, and crime prevention.